Seven problems related to power steering failed have been reported for the 2004 BMW Z4. The most recently reported issues are listed below.
In the spring of 2018 the power steering started to fail becoming stuck, notchy and quickly terrifying to drive. The lack of response, over correction once engaged, overall jumpiness and unpredictability caused me to stop highway driving immediately. Non highway driving ceased within days for the same reasons and it has been in the shop since waiting for a used steering column to become available for $800 instead of $3500 plus install. I bought the car in 2011 with 110,000 miles and it failed at 130,000. My understanding is the engine should be good for another 100,000 easily. This steering failure appears to be common in this car with many garage kept low mileage cars yet to be impacted.
Steering got sticky in a middle of a 90 degree turn nearly resulting in a crash as power steering motor failed temporarily. We understand this is a common problem for this particular BMW vehicle, especially on hot days. Today it was around 85 degrees f. We have owned the car for 5 months and this is the first time this problem occurred, likely because this is the hottest day since the day we bought it in September of last year. We understand that BMW has received almost 50,000 complaints related to this issue and we also understand that NHTSA has seen it fit to close their investigation. We are baffled by this decision as steering problems can be fatal and obviously the defect lies in the manufacturing process and should be corrected by BMW before fatalities start to occur.
The steering on the car becomes 'notchy' and 'twitchy' especially at higher speeds and warm weather. The steering wheel will intermittently stop responding to input for a short range of input, then suddenly start working after a limited range. While driving at high speeds in a straight line, the steering will suddenly pull to one side requiring that the steering wheel is held straight very firm or the car will lunge to the side. The issue was diagnosed by two different BMW repair shops. Both concluded the electronic power steering is failing and the entire steering column needs to be replaced. Estimated repair cost is just under $4,000.
As I backed out of parking space, power assisted steering failed. I managed to drive vehicle with much increased steering effort. It is doubtful that my wife could have managed to drive. Vehicle was towed to dealer where the steering column is being replaced.
When car sits out in the hot sun 100 degrees or better for an extended period of time, is difficult. Steering wheel stays in a tuning position and does not return to center, it sticks in whatever turn you put it in. You must manually force the steering wheel back to center. Just today 10/26/2010 all of the warning lights came on and power steering completely failed while driving and the car would not change gears.
Power steering failure at highway speeds and high temperatures.
The contact owns a 2004 BMW Z4. The contact stated while driving 40 mph the power steering failed and the vehicle became difficult to maneuver. The vehicle was taken to a dealer for diagnosis and the steering column was replaced. Six months after the vehicle was repaired the failure recurred. The recent failure was not repaired. The failure and current mileage was 48,000. Updated 6/25/cn updated 7/1/13 the consumer stated the steering would not return to center by itself. Updated.